xref: /openbmc/linux/drivers/mmc/host/sdhci-pxav2.c (revision b78412b8)
1 /*
2  * Copyright (C) 2010 Marvell International Ltd.
3  *		Zhangfei Gao <zhangfei.gao@marvell.com>
4  *		Kevin Wang <dwang4@marvell.com>
5  *		Jun Nie <njun@marvell.com>
6  *		Qiming Wu <wuqm@marvell.com>
7  *		Philip Rakity <prakity@marvell.com>
8  *
9  * This software is licensed under the terms of the GNU General Public
10  * License version 2, as published by the Free Software Foundation, and
11  * may be copied, distributed, and modified under those terms.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  */
19 
20 #include <linux/err.h>
21 #include <linux/init.h>
22 #include <linux/platform_device.h>
23 #include <linux/clk.h>
24 #include <linux/module.h>
25 #include <linux/io.h>
26 #include <linux/gpio.h>
27 #include <linux/mmc/card.h>
28 #include <linux/mmc/host.h>
29 #include <linux/platform_data/pxa_sdhci.h>
30 #include <linux/slab.h>
31 #include <linux/of.h>
32 #include <linux/of_device.h>
33 
34 #include "sdhci.h"
35 #include "sdhci-pltfm.h"
36 
37 #define SD_FIFO_PARAM		0xe0
38 #define DIS_PAD_SD_CLK_GATE	0x0400 /* Turn on/off Dynamic SD Clock Gating */
39 #define CLK_GATE_ON		0x0200 /* Disable/enable Clock Gate */
40 #define CLK_GATE_CTL		0x0100 /* Clock Gate Control */
41 #define CLK_GATE_SETTING_BITS	(DIS_PAD_SD_CLK_GATE | \
42 		CLK_GATE_ON | CLK_GATE_CTL)
43 
44 #define SD_CLOCK_BURST_SIZE_SETUP	0xe6
45 #define SDCLK_SEL_SHIFT		8
46 #define SDCLK_SEL_MASK		0x3
47 #define SDCLK_DELAY_SHIFT	10
48 #define SDCLK_DELAY_MASK	0x3c
49 
50 #define SD_CE_ATA_2		0xea
51 #define MMC_CARD		0x1000
52 #define MMC_WIDTH		0x0100
53 
54 static void pxav2_reset(struct sdhci_host *host, u8 mask)
55 {
56 	struct platform_device *pdev = to_platform_device(mmc_dev(host->mmc));
57 	struct sdhci_pxa_platdata *pdata = pdev->dev.platform_data;
58 
59 	sdhci_reset(host, mask);
60 
61 	if (mask == SDHCI_RESET_ALL) {
62 		u16 tmp = 0;
63 
64 		/*
65 		 * tune timing of read data/command when crc error happen
66 		 * no performance impact
67 		 */
68 		if (pdata && pdata->clk_delay_sel == 1) {
69 			tmp = readw(host->ioaddr + SD_CLOCK_BURST_SIZE_SETUP);
70 
71 			tmp &= ~(SDCLK_DELAY_MASK << SDCLK_DELAY_SHIFT);
72 			tmp |= (pdata->clk_delay_cycles & SDCLK_DELAY_MASK)
73 				<< SDCLK_DELAY_SHIFT;
74 			tmp &= ~(SDCLK_SEL_MASK << SDCLK_SEL_SHIFT);
75 			tmp |= (1 & SDCLK_SEL_MASK) << SDCLK_SEL_SHIFT;
76 
77 			writew(tmp, host->ioaddr + SD_CLOCK_BURST_SIZE_SETUP);
78 		}
79 
80 		if (pdata && (pdata->flags & PXA_FLAG_ENABLE_CLOCK_GATING)) {
81 			tmp = readw(host->ioaddr + SD_FIFO_PARAM);
82 			tmp &= ~CLK_GATE_SETTING_BITS;
83 			writew(tmp, host->ioaddr + SD_FIFO_PARAM);
84 		} else {
85 			tmp = readw(host->ioaddr + SD_FIFO_PARAM);
86 			tmp &= ~CLK_GATE_SETTING_BITS;
87 			tmp |= CLK_GATE_SETTING_BITS;
88 			writew(tmp, host->ioaddr + SD_FIFO_PARAM);
89 		}
90 	}
91 }
92 
93 static void pxav2_mmc_set_bus_width(struct sdhci_host *host, int width)
94 {
95 	u8 ctrl;
96 	u16 tmp;
97 
98 	ctrl = readb(host->ioaddr + SDHCI_HOST_CONTROL);
99 	tmp = readw(host->ioaddr + SD_CE_ATA_2);
100 	if (width == MMC_BUS_WIDTH_8) {
101 		ctrl &= ~SDHCI_CTRL_4BITBUS;
102 		tmp |= MMC_CARD | MMC_WIDTH;
103 	} else {
104 		tmp &= ~(MMC_CARD | MMC_WIDTH);
105 		if (width == MMC_BUS_WIDTH_4)
106 			ctrl |= SDHCI_CTRL_4BITBUS;
107 		else
108 			ctrl &= ~SDHCI_CTRL_4BITBUS;
109 	}
110 	writew(tmp, host->ioaddr + SD_CE_ATA_2);
111 	writeb(ctrl, host->ioaddr + SDHCI_HOST_CONTROL);
112 }
113 
114 static const struct sdhci_ops pxav2_sdhci_ops = {
115 	.set_clock     = sdhci_set_clock,
116 	.get_max_clock = sdhci_pltfm_clk_get_max_clock,
117 	.set_bus_width = pxav2_mmc_set_bus_width,
118 	.reset         = pxav2_reset,
119 	.set_uhs_signaling = sdhci_set_uhs_signaling,
120 };
121 
122 #ifdef CONFIG_OF
123 static const struct of_device_id sdhci_pxav2_of_match[] = {
124 	{
125 		.compatible = "mrvl,pxav2-mmc",
126 	},
127 	{},
128 };
129 MODULE_DEVICE_TABLE(of, sdhci_pxav2_of_match);
130 
131 static struct sdhci_pxa_platdata *pxav2_get_mmc_pdata(struct device *dev)
132 {
133 	struct sdhci_pxa_platdata *pdata;
134 	struct device_node *np = dev->of_node;
135 	u32 bus_width;
136 	u32 clk_delay_cycles;
137 
138 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
139 	if (!pdata)
140 		return NULL;
141 
142 	if (of_find_property(np, "non-removable", NULL))
143 		pdata->flags |= PXA_FLAG_CARD_PERMANENT;
144 
145 	of_property_read_u32(np, "bus-width", &bus_width);
146 	if (bus_width == 8)
147 		pdata->flags |= PXA_FLAG_SD_8_BIT_CAPABLE_SLOT;
148 
149 	of_property_read_u32(np, "mrvl,clk-delay-cycles", &clk_delay_cycles);
150 	if (clk_delay_cycles > 0) {
151 		pdata->clk_delay_sel = 1;
152 		pdata->clk_delay_cycles = clk_delay_cycles;
153 	}
154 
155 	return pdata;
156 }
157 #else
158 static inline struct sdhci_pxa_platdata *pxav2_get_mmc_pdata(struct device *dev)
159 {
160 	return NULL;
161 }
162 #endif
163 
164 static int sdhci_pxav2_probe(struct platform_device *pdev)
165 {
166 	struct sdhci_pltfm_host *pltfm_host;
167 	struct sdhci_pxa_platdata *pdata = pdev->dev.platform_data;
168 	struct device *dev = &pdev->dev;
169 	struct sdhci_host *host = NULL;
170 	const struct of_device_id *match;
171 
172 	int ret;
173 	struct clk *clk;
174 
175 	host = sdhci_pltfm_init(pdev, NULL, 0);
176 	if (IS_ERR(host))
177 		return PTR_ERR(host);
178 
179 	pltfm_host = sdhci_priv(host);
180 
181 	clk = devm_clk_get(dev, "PXA-SDHCLK");
182 	if (IS_ERR(clk)) {
183 		dev_err(dev, "failed to get io clock\n");
184 		ret = PTR_ERR(clk);
185 		goto free;
186 	}
187 	pltfm_host->clk = clk;
188 	ret = clk_prepare_enable(clk);
189 	if (ret) {
190 		dev_err(&pdev->dev, "failed to enable io clock\n");
191 		goto free;
192 	}
193 
194 	host->quirks = SDHCI_QUIRK_BROKEN_ADMA
195 		| SDHCI_QUIRK_BROKEN_TIMEOUT_VAL
196 		| SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN;
197 
198 	match = of_match_device(of_match_ptr(sdhci_pxav2_of_match), &pdev->dev);
199 	if (match) {
200 		pdata = pxav2_get_mmc_pdata(dev);
201 	}
202 	if (pdata) {
203 		if (pdata->flags & PXA_FLAG_CARD_PERMANENT) {
204 			/* on-chip device */
205 			host->quirks |= SDHCI_QUIRK_BROKEN_CARD_DETECTION;
206 			host->mmc->caps |= MMC_CAP_NONREMOVABLE;
207 		}
208 
209 		/* If slot design supports 8 bit data, indicate this to MMC. */
210 		if (pdata->flags & PXA_FLAG_SD_8_BIT_CAPABLE_SLOT)
211 			host->mmc->caps |= MMC_CAP_8_BIT_DATA;
212 
213 		if (pdata->quirks)
214 			host->quirks |= pdata->quirks;
215 		if (pdata->host_caps)
216 			host->mmc->caps |= pdata->host_caps;
217 		if (pdata->pm_caps)
218 			host->mmc->pm_caps |= pdata->pm_caps;
219 	}
220 
221 	host->ops = &pxav2_sdhci_ops;
222 
223 	ret = sdhci_add_host(host);
224 	if (ret) {
225 		dev_err(&pdev->dev, "failed to add host\n");
226 		goto disable_clk;
227 	}
228 
229 	return 0;
230 
231 disable_clk:
232 	clk_disable_unprepare(clk);
233 free:
234 	sdhci_pltfm_free(pdev);
235 	return ret;
236 }
237 
238 static struct platform_driver sdhci_pxav2_driver = {
239 	.driver		= {
240 		.name	= "sdhci-pxav2",
241 		.of_match_table = of_match_ptr(sdhci_pxav2_of_match),
242 		.pm	= &sdhci_pltfm_pmops,
243 	},
244 	.probe		= sdhci_pxav2_probe,
245 	.remove		= sdhci_pltfm_unregister,
246 };
247 
248 module_platform_driver(sdhci_pxav2_driver);
249 
250 MODULE_DESCRIPTION("SDHCI driver for pxav2");
251 MODULE_AUTHOR("Marvell International Ltd.");
252 MODULE_LICENSE("GPL v2");
253 
254